Chapter 13. Memory, Learning, and Development

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By Jon Cohen Until now, researchers wanting to understand the Neanderthal brain and how it differed from our own had to study a void. The best insights into the neurology of our mysterious, extinct relatives came from analyzing the shape and volume of the spaces inside their fossilized skulls. But a recent marriage of three hot fields—ancient DNA, the genome editor CRISPR, and "organoids" built from stem cells—offers a provocative, if very preliminary, new option. At least two research teams are engineering stem cells to include Neanderthal genes and growing them into "minibrains" that reflect the influence of that ancient DNA. None of this work has been published, but Alysson Muotri, a geneticist at the University of California, San Diego (UCSD) School of Medicine, described his group's Neanderthal organoids for the first time this month at a UCSD conference called Imagination and Human Evolution. His team has coaxed stem cells endowed with Neanderthal DNA into pea-size masses that mimic the cortex, the outer layer of real brains. Compared with cortical minibrains made with typical human cells, the Neanderthal organoids have a different shape and differences in their neuronal networks, including some that may have influenced the species's ability to socialize. "We're trying to recreate Neanderthal minds," Muotri says. Muotri focused on one of approximately 200 protein-coding genes that differ between Neanderthals and modern humans. Known as NOVA1, it plays a role in early brain development in modern humans and also is linked to autism and schizophrenia. Because it controls splicing of RNA from other genes, it likely helped produce more than 100 novel brain proteins in Neanderthals. Conveniently, just one DNA base pair differs between the Neanderthal gene and the modern human one. © 2018 American Association for the Advancement of Science.

Keyword: Development of the Brain; Evolution
Link ID: 25116 - Posted: 06.21.2018

By Sara Goudarzi The presidents of the National Academies of Sciences, Engineering, and Medicine issued a statement Wednesday advocating for the U.S. Department of Homeland Security to stop separating migrant families. The statement cites research that indicates endangerment of those involved. Last week the American Psychological Association released a letter opposing the Trump administration’s policy of taking immigrant children from their parents at the border. Under the zero-tolerance immigration policy, since May more than 2,300 immigrant children—some of them babies—have been forcibly separated from their parents attempting to enter the U.S. from Mexico. Also Wednesday, as the backlash and public outcry continue to grow, Pres. Donald Trump said he would sign an executive order to stop separating families at the order. It was unclear when children already separated might be reunited with their families. But even if reunited soon, medical experts say the effects of separation can potentially last a lifetime. Scientific American spoke with Alan Shapiro, assistant clinical professor in pediatrics at Albert Einstein College of Medicine, about the effects of separation trauma and other health and mental consequences of breaking up families. Shapiro is also senior medical director for Community Pediatric Programs (CPP), a collaboration between the Children’s Hospital at Montefiore in New York City and the Children’s Health Fund, and medical director and co-founder of Terra Firma, a partnership that provides medical and legal services to immigrant children. © 2018 Scientific American

Keyword: Development of the Brain
Link ID: 25115 - Posted: 06.21.2018

By Victoria Davis Some people can trace their traditions back decades; the swamp sparrow has passed its songs down for more than 1500 years. The findings, published today in Nature Communications, suggest humans are not alone in keeping practices alive for long periods of time. To conduct the study, researchers recorded a collection of songs from 615 adult male swamp sparrows from six densely populated areas across the northeastern United States. They dissected each bird’s song repertoire, identifying only 160 different syllable types within all the recorded sample. Most swamp swallows sang the same tunes, using the same common syllables, but there were a few rare types in each population, just as there are variations in human oral histories over time. Using a statistical method of calculation called approximate Bayesian computation and models that measure the diversity of syllable types present in each population, the scientists were able to calculate how the songs of each male would have changed over time. They also found that all but two of the most common syllables used during their sampling in 2009 were also the most common during an earlier study of the species when recordings were made in the 1970s. Overall, the analysis indicated that the average age of the oldest tune dated back about 1537 years. © 2018 American Association for the Advancement of Science

Keyword: Animal Communication; Language
Link ID: 25112 - Posted: 06.21.2018

Maria Temming Getting robots to do what we want would be a lot easier if they could read our minds. That sci-fi dream might not be so far off. With a new robot control system, a human can stop a bot from making a mistake and get the machine back on track using brain waves and simple hand gestures. People who oversee robots in factories, homes or hospitals could use this setup, to be presented at the Robotics: Science and Systems conference on June 28, to ensure bots operate safely and efficiently. Electrodes worn on the head and forearm allow a person to control the robot. The head-worn electrodes detect electrical signals called error-related potentials — which people’s brains unconsciously generate when they see someone goof up — and send an alert to the robot. When the robot receives an error signal, it stops what it is doing. The person can then make hand gestures — detected by arm-worn electrodes that monitor electrical muscle signals — to show the bot what it should do instead. MIT roboticist Daniela Rus and colleagues tested the system with seven volunteers. Each user supervised a robot that moved a drill toward one of three possible targets, each marked by an LED bulb, on a mock airplane fuselage. Whenever the robot zeroed in on the wrong target, the user’s mental error-alert halted the bot. And when the user flicked his or her wrist left or right to redirect the robot, the machine moved toward the proper target. In more than 1,000 trials, the robot initially aimed for the correct target about 70 percent of the time, and with human intervention chose the right target more than 97 percent of the time. The team plans to build a system version that recognizes a wider variety of user movements. That way, “you can gesture how the robot should move, and your motion can be more fluidly interpreted,” says study coauthor Joseph DelPreto, also a roboticist at MIT. |© Society for Science & the Public 2000 - 2018

Keyword: Brain imaging; Robotics
Link ID: 25111 - Posted: 06.20.2018

Siobhan Roberts In May 2013, the mathematician Carina Curto attended a workshop in Arlington, Virginia, on “Physical and Mathematical Principles of Brain Structure and Function” — a brainstorming session about the brain, essentially. The month before, President Obama had issued one of his “Grand Challenges” to the scientific community in announcing the BRAIN Initiative (Brain Research through Advancing Innovative Neurotechnologies), aimed at spurring a long-overdue revolution in understanding our three-pound organ upstairs. In advance of the workshop, the hundred or so attendees each contributed to a white paper addressing the question of what they felt was the most significant obstacle to progress in brain science. Answers ran the gamut — some probed more generally, citing the brain’s “utter complexity,” while others delved into details about the experimental technology. Curto, an associate professor at Pennsylvania State University, took a different approach in her entry, offering an overview of the mathematical and theoretical technology: A major obstacle impeding progress in brain science is the lack of beautiful models. Let me explain. … Many will agree that the existing (and impending) deluge of data in neuroscience needs to be accompanied by advances in computational and theoretical approaches — for how else are we to “make sense” of these data? What such advances should look like, however, is very much up to debate. … How much detail should we be including in our models? … How well can we defend the biological realism of our theories? All Rights Reserved © 2018

Keyword: Robotics; Learning & Memory
Link ID: 25108 - Posted: 06.20.2018

Cassandra Willyard One of the earliest attempts to estimate the number of genes in the human genome involved tipsy geneticists, a bar in Cold Spring Harbor, New York, and pure guesswork. That was in 2000, when a draft human genome sequence was still in the works; geneticists were running a sweepstake on how many genes humans have, and wagers ranged from tens of thousands to hundreds of thousands. Almost two decades later, scientists armed with real data still can’t agree on the number — a knowledge gap that they say hampers efforts to spot disease-related mutations. The latest attempt to plug that gap uses data from hundreds of human tissue samples and was posted on the BioRxiv preprint server on 29 May1. It includes almost 5,000 genes that haven’t previously been spotted — among them nearly 1,200 that carry instructions for making proteins. And the overall tally of more than 21,000 protein-coding genes is a substantial jump from previous estimates, which put the figure at around 20,000. But many geneticists aren’t yet convinced that all the newly proposed genes will stand up to close scrutiny. Their criticisms underscore just how difficult it is to identify new genes, or even define what a gene is. “People have been working hard at this for 20 years, and we still don’t have the answer,” says Steven Salzberg, a computational biologist at Johns Hopkins University in Baltimore, Maryland, whose team produced the latest count. © 2018 Macmillan Publishers Limited

Keyword: Genes & Behavior
Link ID: 25106 - Posted: 06.20.2018

Chris Benderev Stephanie and Natalie enrolled their older son in sessions at a Brain Balance Achievement Center in the hope that it would help him make friends. Hokyoung Kim for NPR Some parents see it coming. Natalie was not that kind of parent. Even after the director and a teacher at her older son's day care sat her down one afternoon in 2011 to detail the 3-year-old's difficulty socializing and his tendency to chatter endlessly about topics his peers showed no interest in, she still didn't get the message. Her son, the two educators eventually spelled out, might be on the autism spectrum. "I was in tears at the end," she says. "When I got home, I was just devastated." Natalie broke the news to her wife, Stephanie, whose mind fast-forwarded to a distressing future. Would her son — a squat, cheerful boy who, despite his affectionate nature, didn't have any playmates — ever be able to make friends? When a doctor eventually confirmed he had an autism spectrum disorder, the diagnosis came with a suggestion: Perhaps the boy would benefit from Prozac when he turned 7. "That was when both of us fell apart in that meeting," Natalie says. For both parents, medication wasn't an option. Article continues after sponsorship "Prozac is a very powerful drug for adults. Why would you give it to a 7-year-old?" Stephanie wondered after the doctor's visit. "I welled up with all of this emotion. And I said I will not let that happen." (To protect their privacy, we are only using Natalie's and Stephanie's first names. We are not naming their children.) The fear of psychotropic drugs led the family to pursue alternative treatments for autism. To start, they dropped gluten. © 2018 npr

Keyword: ADHD; Autism
Link ID: 25104 - Posted: 06.19.2018

Ed Yong Peter, aged 3, was scared of rabbits. So Mary Cover Jones kept bringing him rabbits. At first, she’d take a caged rabbit up to Peter, while he ate some candy and played with other children. At first, Peter was terrified by the mere presence of a rabbit in the same room. But soon, he allowed the animal to get closer—12 feet, then four, then three. Eventually, Peter was happy for rabbits to nibble his fingers. “The case of Peter illustrates how a fear may be removed under laboratory conditions,” Cover Jones wrote in 1924. Cover Jones is now recognized as the "mother of behavioral therapy." Her observations laid the groundwork for what would become known as exposure therapy—the practice of getting people to overcome their fears by facing them in controlled settings. A century later, neuroscientists can watch how the act of facing one’s fears actually plays out inside the brain. Using gene-engineering tools, they can label the exact neurons in a mouse’s brain that store a specific fearful memory. Then, they can watch what happens when the rodent recalls those experiences. By doing this, Ossama Khalaf from the EPFL in Lausanne showed that the extinction of fear depends on reactivating the neurons that encode it. A mouse has to re-experience a deep-rooted fear if it is to lose it. When someone encounters a new experience—say, a terrifying rabbit—groups of neurons in their brain fire together, the connections between them become stronger, and molecules accumulate at the places where neurons meet. Many scientists believe that these preserved patterns of strengthened connections are the literal stuff of memories—the physical representations of the things we remember. These connected neuron groups are called engrams.

Keyword: Emotions; Learning & Memory
Link ID: 25101 - Posted: 06.18.2018

By Jessica Wright, Spectrum o Young people with autism have more psychiatric and medical conditions than do their typical peers or those with attention deficit hyperactivity disorder (ADHD), a new study suggests. The early onset of these problems suggests they do not stem solely from a lifetime of poor healthcare, says lead researcher Lisa Croen, director of the Autism Research Program at Kaiser Permanente, a managed healthcare provider based in California. “One possible explanation is that there’s something physiologic or genetic that’s underlying not only what falls into the definition of autism, but also physical health and, more broadly, mental health,” she says. Some of the problems in young people with autism, such as obesity, may be related to poor diet, medication use and limited physical activity, says Alice Kuo, associate professor of internal medicine and pediatrics at the University of California, Los Angeles, who was not involved in the study. Several studies have documented the co-occurrence of psychiatric and medical conditions in people with autism. Croen’s team published a similar analysis in 2015 of adults with autism aged 18 to 74. (The oldest control was 92.) © 2018 Scientific American

Keyword: Autism
Link ID: 25100 - Posted: 06.18.2018

by Judith Graham You’ve turned 65 and exited middle age. What are the chances you’ll develop cognitive impairment or dementia in the years ahead? New research about “cognitive life expectancy” — how long older adults live with good vs. declining brain health — shows that after age 65, men and women spend more than a dozen years in good cognitive health, on average. And, over the past decade, that time span has been expanding. By contrast, cognitive challenges arise in a more compressed time frame in later life, with mild cognitive impairment (problems with memory, decision-making or thinking skills) lasting about four years, on average, and dementia (Alzheimer’s disease or other related conditions) occurring over 1½ to two years. Even when these conditions surface, many seniors retain an overall sense of well-being, according to new research presented in April at the Population Association of America’s annual meeting. “The majority of cognitively impaired years are happy ones, not unhappy ones,” said Anthony Bardo, a co-author of that study and an assistant professor of sociology at the University of Kentucky at Lexington. Recent research finds that: Most seniors don’t have cognitive impairment or dementia. Of Americans 65 and older, about 20 to 25 percent have mild cognitive impairment while about 10 percent have dementia, according to Kenneth Langa, an expert in the demography of aging and a professor of medicine at the University of Michigan. Risks rise with advanced age, and the portion of the population affected is significantly higher for people older than 85. © 1996-2018 The Washington Post

Keyword: Alzheimers
Link ID: 25099 - Posted: 06.18.2018

By Jan Hoffman One in seven high school students reported misusing prescription opioids, one of several disturbing results in a nationwide survey of teenagers that revealed a growing sense of fear and despair among youth in the United States. The numbers of teenagers reporting “feelings of sadness or hopelessness,” suicidal thoughts, and days absent from school out of fear of violence or bullying have all risen since 2007. The increases were particularly pointed among lesbian, gay and bisexual high school students. Nationally, 1 in 5 students reported being bullied at school; 1 in 10 female students and 1 in 28 male students reported having been physically forced to have sex. “An adolescent’s world can be bleak,” said Dr. Jonathan Mermin, an official with the Centers for Disease Control and Prevention, which conducted the survey and analyzed the data. “But having a high proportion of students report they had persistent feelings of hopelessness and 17 percent considering suicide is deeply disturbing.” In 2017, 31 percent of students surveyed said they had such feelings, while 28 percent said so in 2007. In 2017, nearly 14 percent of students had actually made a suicide plan, up from 11 percent in 2007. The Youth Risk Behavior Survey is given every two years to nearly 15,000 students in high schools in 39 states, and poses questions about a wide array of attitudes and activities. The report did offer some encouraging trends, suggesting that the overall picture for adolescents is a nuanced one. Compared to a decade ago, fewer students reported having had sex, drinking alcohol or using drugs like cocaine, heroin or marijuana. © 2018 The New York Times Company

Keyword: Development of the Brain; Depression
Link ID: 25098 - Posted: 06.18.2018

Darby Saxbe Flinching as a gunshot whizzes past your window. Covering your ears when a police car races down your street, sirens blaring. Walking past a drug deal on your block or a beating at your school. For kids living in picket-fence suburbia, these experiences might be rare. But for their peers in urban poverty, they are all too commonplace. More than half of children and adolescents living in cities have experienced some form of community violence – acts of disturbance or crime, such as drug use, beatings, shootings, stabbings and break-ins, within their neighborhoods or schools. Researchers know from decades of work that exposure to community violence can lead to emotional, social and cognitive problems. Kids might have difficulty regulating emotions, paying attention or concentrating at school. Over time, kids living with the stress of community violence may become less engaged in school, withdraw from friends or show symptoms of post-traumatic stress, like irritability and intrusive thoughts. In short, living in an unsafe community can have a corrosive effect on child development. Few studies, though, have specifically looked at the toll community violence may take on the growing brain. Recently, I studied this question in collaboration with a team of researchers here at the University of Southern California. Our goal: to see whether individuals exposed to more community violence in their early teen years would show differences in the structure and function of their brains in late adolescence. © 2010–2018, The Conversation US, Inc.

Keyword: Aggression; Development of the Brain
Link ID: 25087 - Posted: 06.14.2018

by Sarah DiGiulio Why is it that you can perfectly recite the words to *NSYNC’s “Bye Bye Bye,” but can’t remember the title of the new TV show you started watching on Netflix and wanted to tell your coworker about? We remember things because they either stand out, they relate to and can easily be integrated in our existing knowledge base, or it’s something we retrieve, recount or use repeatedly over time, explains Sean Kang, PhD, assistant professor in the Department of Education at Dartmouth College, whose research focuses on the cognitive psychology of learning and memory. “The average layperson trying to learn nuclear physics for the first time, for example, will probably find it very difficult to retain that information." That's because he or she likely doesn’t have existing knowledge in their brain to connect that new information to. And on a molecular level neuroscientists suspect that there’s actually a physical process that needs to be completed to form a memory — and us not remembering something is a result of that not happening, explains Blake Richards, DPhil, assistant professor in the Department of Biological Sciences and Fellow at the Canadian Institute for Advanced Research. In the same way that when you store a grocery list on a piece of paper, you are making a physical change to that paper by writing words down, or when you store a file on a computer, you’re making a physical change somewhere in the magnetization of some part of your hard drive — a physical change happens in your brain when you store a memory or new information. © 2018 NBC UNIVERSAL

Keyword: Learning & Memory
Link ID: 25085 - Posted: 06.14.2018

By Hannah Furfaro, Spectrum Boys with autism have smaller heads, are shorter and weigh less at birth than their typical peers do—but all that changes by age 3, a new study suggests. The new work is among the first to link autism to rapid skeletal growth. “Mapping physical growth as well as growth in head circumference is really important because it implicates a lot of other mechanisms that might be involved, not just the brain,” says Cheryl Dissanayake, professor of developmental psychology at La Trobe University in Melbourne, Australia, who co-led the work. Advertisement The findings hint that children with autism are smaller in utero, but their growth then accelerates: They catch up and surpass typical children in height and head size between birth and age 3. The results from the new study contrast with those from a 2014 report that found no difference in the rate of head or body growth between infants at risk for autism and controls. But many other studies have found differences in head size in children and adolescents with autism. “It’s now quite clear that growth dysregulation is a key and important phenomenon in autism,” says Eric Courchesne, co-director of the Autism Center of Excellence at the University of California, San Diego, who was not involved in the research. Growth spurt: The researchers reviewed growth charts for 135 boys with autism and 74 typical boys who live in Victoria, Australia. (They excluded children taking medications that affect growth and those born prematurely.) © 2018 Scientific American

Keyword: Autism; Development of the Brain
Link ID: 25078 - Posted: 06.11.2018

By Clyde Haberman For nine frustrating years, Lesley and John Brown tried to conceive a child but failed because of her blocked fallopian tubes. Then in late 1977, this English couple put their hopes in the hands of two men of science. Thus began their leap into the unknown, and into history. On July 25, 1978, the Browns got what they had long wished for with the arrival of a daughter, Louise, a baby like no other the world had seen. She came into being through a process of in vitro fertilization developed by Robert G. Edwards and Patrick Steptoe. Her father’s sperm was mixed with her mother’s egg in a petri dish, and the resulting embryo was then implanted into the womb for normal development. Louise was widely, glibly and incorrectly called a “test-tube baby.” The label was enough to throw millions of people into a moral panic, for it filled them with visions of Dr. Frankenstein playing God and throwing the natural order of the universe out of kilter. The reality proved far more benign, maybe best captured by Grace MacDonald, a Scottish woman who in January 1979 gave birth to the second in vitro baby, a boy named Alastair. Nothing unethical was at work, she told the BBC in 2003. “It’s just nature being given a helping hand.” In this installment of its video documentaries, Retro Report explores how major news stories of the past shape current events by harking back to Louise Brown’s birth. If anything, more modern developments in genetics have raised the moral, ethical and political stakes. But the fundamental questions are essentially what they were in the 1970s with the advent of in vitro fertilization: Are these welcome advances that can only benefit civilization? Or are they incursions into an unholy realm, one of “designer babies,” with potentially frightening consequences? In vitro fertilization, or I.V.F., is by now broadly accepted, though it still has objectors, including the Roman Catholic Church. Worldwide, the procedure has produced an estimated six million babies, and is believed to account for 3 percent of all live births in some developed countries. Designer-baby fears have proved in the main to be “overblown,” said Dr. Paula Amato, a professor of obstetrics and gynecology at Oregon Health & Science University in Portland. “We have not seen it with I.V.F. in general,” she told Retro Report. “We have not seen it with P.G.D.” © 2018 The New York Times Company

Keyword: Development of the Brain; Genes & Behavior
Link ID: 25077 - Posted: 06.11.2018

by Anthea Rowan When Mike Shooter was in medical school, he suffered the first of what he calls “thunderous depressions.” More followed. Shooter’s efforts to come to grips with these experiences has made him acutely aware of what young people with mental-health problems endure and forged his career as a preeminent child psychiatrist in England. He was the first such specialist to be elected president of the Royal College of Psychiatrists, a position he held from 2002 to 2005. Recently he published “Growing Pains,” which is based on 40 years of working with young people. The book explains why it’s imperative to differentiate between depression and the ordinary but often intense difficulties some children face. He recently spoke with The Washington Post on these issues. This transcript was edited for clarity and length. Q: Do you think young people are more vulnerable to mental illness now? A: Research suggests that the United Kingdom is the least happy place for a child to be brought up in the Western world; America cannot be far behind. Some of this could be attributed to the grinding effect of poverty. But not all: The frenetic competition, in school, in the scramble for jobs, in peer-group relationships, means many children fall off the bottom of the ladder of competition and feel as if they’ve failed. Or are so unsure of their own worth that they sit up all night searching for “likes” on social media in lieu of proper friendships. But it’s not all bad news. There is currently much research into resilience: what enables some children to cope while others do not. I know from experience that there is one thing that can make all the difference: a relationship with an adult close enough to them, that supports them, listens to their distress and treats them as worthwhile. That person could be a relative, a family friend, a teacher or, dare I say it, a child psychiatrist. © 1996-2018 The Washington Post

Keyword: Depression; Development of the Brain
Link ID: 25074 - Posted: 06.11.2018

Aimee Cunningham American kids with food allergies are more than twice as likely to have autism spectrum disorder as kids without, a study of national health data finds. The population-based finding adds to experimental evidence that there may be a connection between false steps or overreactions by the immune system and the neurodevelopmental disorder. Researchers looked only for an association between allergies and autism spectrum disorder, or ASD, among a total of 199,520 children ages 3 to 17 surveyed from 1997 to 2016 as part of the U.S. National Health Interview Survey. The study was not designed to discover what may be behind the link. The team found that, out of 1,868 children with autism, 216 had a food allergy — or about 11 percent. By comparison, only about 4 percent of children without autism had a food allergy, the researchers report online June 8 in JAMA Network Open. Kids with autism were also more likely to have respiratory or skin allergies like eczema than kids without autism. The number of children with autism has more than doubled since 2000, to a prevalence of 16.8 per 1,000 kids. Meanwhile, the number of kids with food allergies rose from 3.4 percent in 1997–1999 to 5.1 percent in 2009–2011. It is unknown whether developing food allergies may contribute to the development of autism, or vice versa, or if something else is causing both, says study coauthor and epidemiologist Wei Bao of the University of Iowa’s College of Public Health in Iowa City. “The causes of ASD remain unclear,” he says. |© Society for Science & the Public 2000 - 2018.

Keyword: Autism; Neuroimmunology
Link ID: 25072 - Posted: 06.09.2018

/ By Michael Schulson Biswaroop Roy Chowdhury is an Indian engineer with, he says, an honorary Ph.D. in diabetes science from Alliance International University, a school in Zambia that bears many of the hallmarks of an online scam. He runs a small nutrition clinic near Delhi. Two months ago, Chowdhury posted a brief video on YouTube arguing that HIV is not real, and that anti-retroviral medication actually causes AIDS. He offered to inject himself with the blood of someone who had tested positive. Within weeks, the video had more than 380,000 views on YouTube. Tens of thousands more people watched on Facebook. Most of the viewers appear to be in India, where some 60,000 people die of HIV-related causes each year. After the March video, Chowdhury kept on posting. Follow-up videos on HIV racked up hundreds of thousands more hits. He also distributed copies of an ebook titled “HIV-AIDS: The Greatest Lie of 21st Century.” When I spoke with Chowdhury by phone last month, he claimed that 700 people had gotten in touch to say they had gone off their HIV medications. The actual number, he added, might be even higher. “We don’t know what people are doing on their own. I can only tell you about the people who report to us,” he said. Chowdhury’s figures are impossible to verify, but his skills with digital media are apparent — as are the troubling questions they raise about the role of Silicon Valley platforms in spreading misinformation. Such concerns, of course, aren’t new: Over the past two years, consumers, lawmakers, and media integrity advocates in the United States and Europe have become increasingly alarmed at the speed with which incendiary, inaccurate, and often deliberately false content spreads on sites like Facebook and YouTube — the latter a Google subsidiary. Copyright 2018 Undark

Keyword: Autism
Link ID: 25065 - Posted: 06.07.2018

By Douglas Woods It often starts with a simple, subtle behavior like a rapid eye blink. Sometimes it’s a nose-scrunch or a sniff that is confused with a lingering cold or an allergy. Often, these habits go away on their own, but in about 1 percent of children (boys more so than girls), these blinks, twitches, and coughs become the persistent tic disorder known as Tourette syndrome (TS), a misunderstood and stigmatizing neurological condition. Media portrayals of TS often overemphasize the rare (fewer than 15 percent of cases) symptoms, in which people with TS shout obscene words—a symptom known as coprolalia—but most patients have a wide range of movements and sounds, ranging from simple tics to more complex ones that often look intentional but are not. Hidden beneath the tics, people with TS often experience "premonitory urges”—unpleasant sensations that build until the tic occurs. Ticcing brings a brief sense of relief, but the urges soon return. We know that TS is a genetically-based neurological disorder that is strongly influenced by a person’s surroundings. The disorder stems from a problem within the basal ganglia, a series of structures in the brain that are responsible for selecting and inhibiting our movements. When neurons fire, signaling us to move, the basal ganglia serves as a filter, allowing some of these signals to pass through and become movements. Other movement signals that are not needed in a particular situation are held back. © 2018 Scientific American

Keyword: Tourettes; Learning & Memory
Link ID: 25062 - Posted: 06.06.2018

By Ruth Williams The sun’s ultraviolet (UV) radiation is a major cause of skin cancer, but it offers some health benefits too, such as boosting production of essential vitamin D and improving mood. Today (May 17), a report in Cell adds enhanced learning and memory to UV’s unexpected benefits. Researchers have discovered that, in mice, exposure to UV light activates a molecular pathway that increases production of the brain chemical glutamate, heightening the animals’ ability to learn and remember. “The subject is of strong interest, because it provides additional support for the recently proposed theory of ultraviolet light’s regulation of the brain and central neuroendocrine system,” dermatologist Andrzej Slominski of the University of Alabama who was not involved in the research writes in an email to The Scientist. “It’s an interesting and timely paper investigating the skin-brain connection,” notes skin scientist Martin Steinhoff of University College Dublin’s Center for Biomedical Engineering who also did not participate in the research. “The authors make an interesting observation linking moderate UV exposure to . . . [production of] the molecule urocanic acid. They hypothesize that this molecule enters the brain, activates glutaminergic neurons through glutamate release, and that memory and learning are increased.” © 1986-2018 The Scientist

Keyword: Learning & Memory; Biological Rhythms
Link ID: 25052 - Posted: 06.02.2018